The present invention relates to a composite cover material which may be used by itself or in conjunction with absorbent articles and a process for making the same. More particularly, it relates to a cover material made of a perforated thermoplastic film with an external layer of fluid pervious nonwoven material having a plurality of locally densified and fused areas in vertical alignment with the perforations in the film. The densified and fused areas act to mask the perforations in the film. These same areas also act to partially block the perforations in the film when the cover material is compressed, thereby restricting fluid flow through the area under compression.
Most absorbent articles used in personal care products and other areas employ a cover material to contain and protect the absorbent material which is typically found in the interior of the product. Examples of such absorbent products include infant and adult diapers, medical bandaging and feminine sanitary products such as sanitary pads. The bulk of these products sold today are disposable, single use items. As a result, achieving maximum performance at a minimal cost is important in the design and acceptance of the product.
Acceptance of a product is not only dependent upon actual attributes but upon the user's perception of the product as well. For example, with feminine sanitary pads, not only must the product physically keep the user clean and dry, the user must perceive that the product is yielding these results. Otherwise the user will reject the product even though it is fulfilling its intended purpose.
Typically, absorbent articles include a bodyside cover, an absorbent interior and an external cover material or baffle to lessen or prevent leakage. In order to maximize performance of the absorbent article, the bodyside cover material must allow for the rapid transfer of fluid through itself and into the absorbent layer below. Once the fluid has been transferred to the absorbent layer, the cover material should present a clean and dry feel to the user. Nonwoven cover materials are frequently used in an attempt to achieve these properties. However, lightweight nonwovens, as are commonly used in such products, have poor masking capabilities and a limited ability to prevent rewetting once the fluid has been transferred to the absorbent layer. As a result, these cover materials may additionally employ a perforated film positioned between the nonwoven and the absorbent pad to form a two-piece cover material. To a certain degree, the film masks the absorbed fluid from the user's view and restricts backflow of fluid previously transferred to the absorbent layer. Examples of such materials can be found in U.S. Pat. Nos. 3,965,906, 3,994,299 and 4,014,341. However, given the relative number and size of holes that are needed to affect good fluid transfer into the absorbent layer, fluid flowback and masking are still a problem, especially in the case of menses with sanitary pads and urine with diapers.
It is, therefore, an object of the present invention to provide a cover material for absorbent articles and other uses which is comfortable while providing good masking characteristics.
It is another object of the present invention to provide a cover material with reduced fluid backflow or rewet when under compression.
These and other objects of the invention will become more apparent upon a further review of the accompanying specification, drawings and claims.